Ramos / Ramos-luc Orthotopic Mouse Model Service for Lymphoma

The Ramos / Ramos-luc orthotopic mouse model of lymphoma engrafts a molecularly archetypal human Burkitt lymphoma — EBV-negative, MYC-translocated, CD20-positive — into the hematolymphoid system of immunodeficient mice, where disseminated disease can be quantified in real time by whole-body luciferase bioluminescence. Alfa Cytology delivers this platform as an integrated preclinical service: authenticated CRL-1596 banking, Ramos-luc reporter line qualification, tail-vein or tumor-bed engraftment in SCID/NSG recipients, scheduled in vivo imaging, dosing of antibodies, ADCs, CAR-T cells, or small molecules, and endpoints combining survival, human-engraftment flow cytometry, and histopathology.

Overview of Ramos / Ramos-luc Orthotopic Mouse Model for Lymphoma

Ramos is a human Burkitt lymphoma cell line established in the mid-1970s by Klein and colleagues from the ascitic fluid of a 3-year-old male patient with American-type Burkitt lymphoma, and it holds a special place in tumor virology: it was the first EBV-genome-negative Burkitt lymphoma line characterized in detail, proving that the tumor could exist without the virus even while the cells carried EBV receptors and could be converted into permanent EBV-positive sublines by in vitro infection. Genetically, Ramos carries the Burkitt-defining t(8;14)(q22;q32) translocation placing MYC under the IGH enhancer, plus TP53 mutation; immunophenotypically it is a mature B cell expressing surface IgM with lambda light chains — it is BCR-dependent, secretes IgM, expresses CD10, CD19, and CD20, and displays roughly 1,500 IL-4 binding sites per cell through its IL-4 receptor and CD23. Its hypodiploid karyotype (modal number 45) and doubling time of about 48 hours round out a molecular identity that has made Ramos a reference reagent far beyond oncology — the Ramos.2G6.4C10 subline is the standard bioassay for interleukin-4.

Fig 1. Comparative characterization showing Ramos CD19-WT (82.7% CD19⁺, 43,800 MFI) versus Ramos CD19-Low (77.1% CD19⁺, 1,655 MFI) cells, with 3D spheroid growth assays demonstrating that ARI0003 co-transduced CD19/BCMA CAR-T cells controlled mGFP⁺ Ramos tumor outgrowth better than single-CAR or pooled constructs across both CD19 densities. (Bachiller, Mireia, et al., 2025)

As an in vivo model, Ramos engrafts efficiently in immunodeficient mice, forming both flank tumors and — more importantly for lymphoma biology — disseminated disease that seeds spleen, lymph nodes, bone marrow, and blood after intravenous delivery. Luciferase-tagged Ramos lines, generated by lentiviral transduction with puromycin-selected reporters, allow serial whole-body bioluminescence imaging after D-luciferin administration, so disseminated burden is quantified non-invasively from engraftment through treatment and relapse. The line’s CD20 and CD19 expression has made it the default substrate for anti-CD20 antibody and antibody-drug conjugate benchmarking, CD19/CD20 CAR-T evaluation, and immunotoxin programs, while its EBV-negative status keeps virus-driven variables out of immune-therapeutic readouts. Together, these properties make the Ramos-luc orthotopic platform the workhorse human B-cell lymphoma system for dissemination kinetics, targeted-therapy efficacy, and human-engraftment studies in preclinical hematologic oncology.

Cell Line Information: Ramos / Ramos-luc

Ramos is one of the most cited human Burkitt lymphoma lines, distinguished by its EBV-negative status and mature B-cell immunophenotype. Its luciferase derivative extends it into imaging-guided in vivo studies. Core attributes follow.

Our Services

Disseminated lymphoma studies live and die by engraftment consistency — and by whether the imaging signal faithfully tracks the human tumor. Alfa Cytology controls both ends: authenticated CRL-1596 master banks expanded at low passage, Ramos-luc lots released only after uniform in vitro luminescence is demonstrated, and tail-vein or tumor-bed engraftment executed under written SOPs. Imaging runs on fixed calendars matched to the model’s roughly 48-hour doubling kinetics, randomized arms start from matched photon flux, and human CD19/CD20 flow cytometry validates engraftment independently of the optical signal. Across the full Ramos / Ramos-luc orthotopic workflow, Alfa Cytology keeps every variable that matters under single-point control.

Workflow of Ramos / Ramos-luc Orthotopic Mouse Model Construction

The Ramos-luc orthotopic workflow centers on disseminated engraftment and imaging-guided monitoring of systemic Burkitt lymphoma, with survival and human-engraftment analyses closing the loop. The sequence below is the standard construction-to-analysis flow.

1. Authentication and reporter release: Ramos / Ramos-luc stocks are expanded from authenticated CRL-1596 master banks at low passage, mycoplasma-tested, and released only after uniform firefly luciferase expression is confirmed by serial in vitro luminescence assay.
2. Engraftment cell preparation: Suspension cultures maintained at 2×10⁵ to 1×10⁶ cells/mL are harvested in log phase, washed, counted, and resuspended in sterile PBS at the challenge dose (commonly 1×10⁶ to 5×10⁶ cells in 100 µL per mouse for tail-vein delivery).
3. Recipient preparation and inoculation: SCID or NSG mice are acclimatized, body-weight stratified, and injected via the lateral tail vein using warming-assisted vessel access; subcutaneous flank cohorts are prepared in parallel where tumor-bed readouts are designed.
4. Engraftment confirmation and baseline imaging: Within the first week, intraperitoneal D-luciferin and whole-body imaging confirm systemic seeding and quantify baseline disseminated burden per animal.
5. Signal-matched randomization and dosing: Animals are allocated to arms with matched photon flux, and treatment begins — anti-CD20 antibodies, ADCs, bispecifics, CAR-T cells, chemotherapy, or combinations — according to the study plan.
6. Serial burden monitoring: Whole-body imaging repeats at protocol-defined intervals alongside body weight and clinical scoring, generating per-animal progression curves and early detection of response or relapse.
7. Human-engraftment analysis and survival endpoints: Peripheral blood, spleen, bone marrow, and lymph nodes are sampled for human CD19/CD20 flow cytometry; morbidity-defined survival feeds Kaplan-Meier analysis; organs are imaged ex vivo, weighed, and preserved for histopathological confirmation of Burkitt lymphoma involvement.

Fig 2. Ramos / Ramos-luc orthotopic mouse model construction workflow.

Case Study-Ramos / Ramos-luc Orthotopic Mouse Model Development

Alfa Cytology has implemented the Ramos-luc orthotopic platform in preclinical programs spanning anti-CD20 antibody and ADC benchmarking, CD19/CD20 CAR-T cell evaluation, and combination-chemotherapy strategies in B-cell lymphoma. In these studies, serial whole-body bioluminescence tracked disseminated burden from engraftment through treatment and relapse, signal-matched randomization balanced arms at matched baseline disease, and terminal analyses combined Kaplan-Meier survival with human CD19/CD20 flow-cytometric engraftment quantification and histopathological confirmation. Reference-arm designs aligned with the model’s established CD20-targeting literature where programs called for them. Study-specific parameters and outcomes are retained as sponsor-confidential deliverables, and representative outlines can be furnished upon request.

Why Choose Alfa Cytology?

A disseminated Burkitt model rewards operational rigor: engraftment consistency, imaging discipline, and B-cell-specific readouts must all hold together. Alfa Cytology’s Ramos-luc service is built to keep them aligned. Sponsors benefit from:

• Authenticated CRL-1596 stocks at low passage with verified luciferase output before study release.
• EBV-negative Burkitt background that removes virus-driven confounders from immune-therapeutic readouts.
• Mature B-cell immunophenotype (CD19/CD20/CD10, surface IgM) natively suited to antibody, ADC, and CAR-T programs.
• Signal-matched randomization across disseminated arms starting from matched photon flux.
• Imaging cadences calibrated to the model’s ~48-hour doubling kinetics.
• Independent human-engraftment validation by CD19/CD20 flow cytometry alongside optical imaging.
• Single-point study accountability with per-timepoint reporting from inoculation through survival analysis.

Contact Us

Advancing a CD20/CD19-targeted program, an ADC, or a CAR-T candidate against B-cell lymphoma? Contact us to discuss challenge doses, engraftment routes, and endpoint panels for the Ramos / Ramos-luc orthotopic platform. You can also reach out to Alfa Cytology for a customized proposal and quotation — our preclinical team will respond with a study design aligned to your modality and timeline.

For research use only. Not intended for any clinical use.